A strong storm system barreling through the South on Friday killed an 8-year-old girl in Florida and threatened to bring tornadoes to large parts of the Carolinas and southern Virginia.

A tree fell onto a house in Woodville, Fla., south of Tallahassee, killing the girl and injuring a 12-year-old boy, according to the Leon County Sheriff’s Office. The office said in a statement that the girl died at a hospital and the boy suffered non-life-threatening injuries. Their names weren’t immediately released.

The same storm system was blamed for the deaths a day earlier of two Mississippi drivers and a woman in Alabama.

The threat on Friday shifted farther east, where tornado warnings covered parts of northeast Georgia, the Carolinas and Virginia.

The national Storm Prediction Center said 9.7 million people in the Carolinas and Virginia were at a moderate risk of severe weather. It’s a region that includes the Charlotte, N.C., metro area.

Torrential downpours, large hail and a few tornadoes were among the hazards, the National Weather Service in Raleigh, N.C., warned.

Radar readings appeared to show a tornado formed in the western Virginia county of Franklin south of Roanoke, though damage on the ground still must be assessed, said National Weather Service meteorologist Phil Hysell. In South Carolina, authorities urged motorists to avoid part of Interstate 26 — the main artery from upstate through Columbia and all the way to Charleston — because downed trees had left the roadway scattered with debris.

In Georgia, the storm system knocked down trees, caused flooding and cut off power to tens of thousands of residents.

A tree came down on an apartment complex in an Atlanta suburb, but only one person reported a minor injury and was treated at the scene, Gwinnett County fire spokesman Capt. Tommy Rutledge told the Atlanta Journal-Constitution.

In Forsyth County northeast of Atlanta, three firefighters suffered minor injuries when their firetruck overturned during heavy rain and wind, Fire Department Division Chief Jason Shivers told the newspaper.

National Weather Service forecasters said they believed the storm system generated multiple tornadoes in southwest and central Mississippi on Thursday, although they won’t be sure until the damage is surveyed. Heavy winds also were reported in Louisiana earlier in the day and in central Alabama as the system quickly pushed eastward.

Damage from the storm system was reported in at least 24 of Mississippi’s 82 counties.